Quality of life (QOL) is increasingly being recognized as an important determinant and outcome of prostate cancer treatment. It is now recommended that decisions about prostate cancer treatment be made based on the potential QOL impact as well as clinical factors and patient characteristics. Recent studies suggest that the patient's ethnic background may also influence QOL outcomes; however, limited information is available on the determinants of ethnic differences in QOL outcomes among prostate cancer patients. It is likely that ethnic differences in QOL are due to a combination of cultural, psychological, behavioral, and socio-environmental factors in addition to differences in treatment patterns and disease characteristics. To increase knowledge of the factors that contribute to disparities in QOL among African American and Caucasian prostate cancer patients, we propose to conduct a longitudinal study of 250 African American and 250 Caucasian men newly diagnosed with prostate cancer. The specific aims of the proposed study are to: (1) compare quality of life outcomes among African American and Caucasian men newly diagnosed with prostate cancer; (2) examine the determinants of ethnic differences in quality of life; (3) to explore the processes of coping with prostate cancer in African American and Caucasian prostate cancer patients. We predict that compared to Caucasian men, African American men will report lower levels of general and prostate-specific QOL following treatment and will recover more slowly. We also predict that environmental stressors and cultural factors will have a greater impact on QOL among African American than among Caucasian men. We also predict that among both African American and Caucasian men, greater perceptions of stress, higher levels of self-efficacy, and use of problem-focused coping strategies will be associated with improved quality of life. Subjects will be recruited from the University of Pennsylvania Medical Center and community-based urology practices within 2-months of diagnosis. Following enrollment, subjects will complete a baseline telephone interview to evaluate demographics, socio-environmental factors, and QOL. Follow-up evaluations will be completed 3-, 6-, and 12-months following the baseline to assess changes in QOL. Repeated measures analysis of variance and multiple linear regression will be conducted to evaluate changes in QOL and to identify factors having independent associations with these outcomes.